I have a pair of these amplifiers, one of them I obtained much later than the other.
I have no idea which revision they are, but one of them have the metal 12A6 tubes, and the other has the 12V6 glass tubes. Neither of them have the pre-amp tube installed, and have a little metal plug into the tube hole.
So, I would like to rebuild these guys to match. so both have 12V6 tubes, and I have read that the transformers are a weak point here. So I ordered a small little 12v transformer I can stuff under the chassis to help offload some of the filament current.
Also, I would like to populate that pre-amp tube for a magnetic RIAA phono pre-amp, So I looked at the Heathkit schematics, but again there are multiple revisions and then I dont know what the pre-amp actually is. whether its phono or not, or for what cartridge.
any ideas? thanks!
I have no idea which revision they are, but one of them have the metal 12A6 tubes, and the other has the 12V6 glass tubes. Neither of them have the pre-amp tube installed, and have a little metal plug into the tube hole.
So, I would like to rebuild these guys to match. so both have 12V6 tubes, and I have read that the transformers are a weak point here. So I ordered a small little 12v transformer I can stuff under the chassis to help offload some of the filament current.
Also, I would like to populate that pre-amp tube for a magnetic RIAA phono pre-amp, So I looked at the Heathkit schematics, but again there are multiple revisions and then I dont know what the pre-amp actually is. whether its phono or not, or for what cartridge.
any ideas? thanks!